the southwest monsoon is active over a large geographical area of India. At least 80% of the country last week reported widespread rainfall, with heavy to very heavy spells lashing Assam, West Bengal, Uttar Pradesh, Uttarakhand, Gujarat, coastal Maharashtra and Karnataka, Kerala, and Lakshadweep.

FACTORS RESPONSIBLE

Factors Causing Increased Rainfall explained for UPSC There have been two main contributors to the enhanced rainfall. (1) The continuous incoming of moisture-laden strong westerly winds from the Arabian Sea. (2) The position of the monsoon trough: a semi-permanent, low-pressure area Extending between Pakistan and the Bay of Bengal during the monsoon season — which usually oscillates between north and south within the season. Factors Causing Increased Rainfall explained for UPSC
  • Whenever it moves towards the south, as it has done in the present case, more rainfall can take place in central, eastern and peninsular india.
  • When it shifts towards the north, the Himalayan foothills are likely to receive more rainfall but the rest of India sees a drop in rainfall.

ARE THERE ANY OTHER FACTORS?

  • The persistence of an offshore trough (a shallow trough of low pressure, which develops along India’s coast during the monsoon) between south gujarat and north kerala for more than a week now.
  • The intermittent development of a wind shear zone — where winds move with different velocities and directions — along latitudes 20 ° N between central and peninsular India.
  • The development of a low pressure system over the west-central Bay of Bengal, off the Odisha coast, on The system moved over Chhattisgarh and adjoining Vidarbha on Tuesday, and over southeast Madhya Pradesh on Wednesday.